Im getting the delivery failed from the post master reply. i don't want it. because then poeple can find out all my real users on the exchange. also, i have a lot of users (10K) in my application - and i don't want to create a mailbox for each user.
is it possible to get this done in ex2010 sp1. hub-transport configuration? or i must use edge-transport as indicated in http://technet.microsoft.com/en-us/library/bb691132(EXCHG.80).aspx